Improvement in dampers



UNITED STATES PATENT OFFICE.

EDWARD BOURNE AND JOHN BOURNE, 0F PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN DAMPERS.

Specification forming part of Letters Patent No. 37,947. dated March 24, 1863.

To all whom it may concern:

Be it known that we, EDWARD BOURNE and JOHN BOURNE, of the city of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Regulating the Draft of furnaces; and we do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, which form part ofthis specification, and to the letters of reference marked thereon, in which- Figure 1 represents a perspective view of a boiler or furnace with our improved draftregulating doors attached. Fig.2 is a perspective view of one of the doors with its appropriate frame detached from the boiler. This door is represented as standing open, the better to show its mode of working. Fig. 8 is a vertical section of the same.

All the parts are lettered, and similar letters indicate like parts on all the figures.

The object of our invention is to obtain a perfectly regulated draft, so as to prevent a greater combustion of fuel than is just sufficient to produce the required amount of steam to accomplish the object for which it is in tended.

The nature of our invention consists in providing the supply and ash-pit doors of a steam boiler with a series of radial apertures for the admission of air, and applying thereto oscillat ing disks, having corresponding apertures, and so attaching or connecting them together that the movement of one changes the position of both, and causes the draft to pass above or below the fire, as the pressure of steam increases or diminishes.

To enable others skilled in the art to make and use our improvements, we will proceed to describe its construction and operation.

The boiler A is constructed in any of the known forms, with the usual appliances and appendages of other such boilers; but in order to regulate the draft, and thereby keep the steam always at the same pressure, we make the supply and ash'pit doors g g precisely alike, and so as to fit perfectly tight upon their respective framesN N. Through these doors are a series of radial openings, on m m m m m, for the admission of air. On a pivot, p, in the center of each door, works an oscillating disk, D, with openings correspondin gin shape and size to those before mentioned. Each of these disks is provided with atoothed segment, 0, which matches in a circular raclQS, attached to a vertical moving rod, R, passing through the hinges P l of the doors. As the rod is moved up, the disks D are moved, one opening the apertures in the supply-door, and the other closing those in the door of the ashpit, causing the draft to pass over the fire, instead of beneath it. As the rod descends the change of draft is effected by reversing the relative position of the disks. The rod R for working the parts is intended to be operated by the same plan as that shown in the patent granted to us on the 13th day of January, 1863, this being merely an improvement in the mode of admitting the air.

In the patent before mentioned the doors open and close by the rod. In this the doors remain stationary, while the air passes through openings or apertures made therein, which is considered infinitely better, as in that case the elevation or opening of the doors for the purpose of firing up or cleaning out, as the case might be, causes a very perceptible variation in the working mechanism, while the doors, from the manner in which they were attached to their frames, made them liable to be broken by the constant falling on the le vers and frames when in the act of closing, while in this case the doors can be opened and closed without changing the position of the workingrod, as the toothed segments on the disks travel around the circular rack on the rod, irrespective of their position.

Having thus described our invention, what we claim, is

1. Moving the disks on the doors by means of the rod passing through their hinges, in combination with the frame thereof, in the manner as herein set forth.

2. Combining the disks with the rod by means of the toothed segments and the circular racks, so as to admit of the doors being opened and closed, without being affected by the mechanism of the parts.

EDWARD BOURNE. JOHN BOURNE. Witnesses:

J. W. ELLs, JOHN MoKENNA, 

